522 COLEOPTEKA OF XORTH AMERICA. 



obliquely rounded at the apex, and finely feerrate ; the third joint 

 of the tarsi is not bilobed, and the fourth, though small, is dis- 

 tinct. The basal margin of the elytra is acute and serrate. 

 Two genera occur in our fauna : — 



Eyes slightly emarginate, fuiiicle attach(!(l at tin; side of tlie club, outer 

 joints slender. . Chramesus. 



Eyes completely divided, funicle attached at the end of the club, outer 

 joints gradually stouter. Polygraphus, 



Chramesus has priority over BJiopalopIeurufi Chapuis; two 

 species occur in Carya in the Atlantic States. Polygrajjliiis 

 rufijoennis extends from Georgia and Canada to Alaska. 



Group 11. — PhlcEotribi. 



This group is intermediate between the preceding and the fol- 

 lowing, and differs from both by the antennal club being composed 

 of three separate joints, which in Phloeotribus form a lamellate 

 mas's, and in the European genus Phloeophthorus a loosely articu- 

 late club as in many Clavicornia. Dr. Chapuis describes the 

 antennaj as frontal; but we see no special difference in their posi- 

 tion from that observed in the preceding and following groups. 

 The head is but very little prolonged in front of the eyes, and 

 there is no preocular groove for the reception of the scape of tho 

 antenniB such as is observed in the two following groups. The 

 tibite are dilated, compressed, obliquely rounded and serrate at 

 tip, with the inner angle slightly niucronate ; the tarsi have the 

 joints 1-3 short, gradually a little wider; third not "emarginate ; 

 fourth very small ; fifth as long as the others united, with diver- 

 gent simple claws. The basal margin of the elytra is acute and 

 serrate. 



But one genus, Thlojotribus, is represented in our fauna, in 

 the Atlantic region. 



Group 111. — Hylurgi. 



In this group the form varies from oval to cylindrical ; the 

 nntennte are inserted at the sides of the front, immediately before 

 the eyes, which are large, transverse, slightly or not at all emar- 

 ginate, and finely granulated. The scape of the antennte is long, 

 and is received in a narrow, transverse groove in front of the 

 eyes; this groove becomes more develoj)ed in the next group, but 

 is not appareut in the preceding groups or tribes; the mandibles 



